The 3M Speedglas Welding Helmet 9100 QR with Rail was designed to fit many of the industry's hard hats. (Hard hat and ADF sold separately.)The 3M Speedglas Welding Helmet 9100 QR with Rail was designed to fit many of the industry’s hard hats. With the QR rail installed on a compatible hard hat, you can easily detach the welding helmet while your hard hat remains in place as you perform non welding tasks. (Hardhat and ADF sold separately.)